Palle Örbaek

Incidence of shoulder and neck pain in a working population: effect modification between mechanical and psychosocial exposures at work? Results from a one year follow up of the Malmö shoulder and neck study cohort

Study objective: To assess the impact of mechanical exposure and work related psychosocial factors on shoulder and neck pain. Design: A prospective cohort study. Participants: 4919 randomly chosen, vocationally active men and women ages 45–65 residing in a Swedish city. Neck and shoulder pain were determined by the standardised Nordic questionnaire. Mechanical exposure was assessed by an index based on 11 items designed and evaluated for shoulder and neck disorders. Work related psychosocial factors were measured by the Karasek and Theorell demand-control instrument. Main results: High mechanical exposure was associated with heightened risk for shoulder and neck pain among men and women during follow up. Age adjusted odds ratios (OR) were 2.17 (95% confidence intervals (CI): 1.65, 2.85) and 1.59 (95% CI: 1.22, 2.06), respectively. In women, job strain (high psychological job demands and low job decision latitude) correlated with heightened risk (OR = 1.73, 95% CI: 1.29, 2.31). These risk estimates remained statistically significant when controlled for high mechanical exposure regarding job strain (and vice versa), and for sociodemographic factors. Testing for effect modification between high mechanical exposure and job strain showed them acting synergistically only in women. Conclusion: Job related mechanical exposure in both sexes, and psychosocial factors in women, seem independently of each other to play a part for development of shoulder and neck pain in vocationally active people. The effect of psychosocial factors was more prominent in women, which could be the result of biological factors as well as gender issues. These results suggest that interventions aiming at reducing the occurrence of shoulder and neck pain should include both mechanical and psychosocial factors.

Determination of cortisol in human saliva using liquid chromatography–electrospray tandem mass spectrometry

The aim of this work was to develop a method for determination of cortisol in saliva by liquid chromatography-tandem mass spectrometry (LC-MS-MS). Saliva was sampled on Salivette tubes. These were centrifuged, deuterium-labeled cortisol was added as internal standard and the proteins precipitated by acetonitrile. The supernatant was evaporated, dissolved in methanol acidified with acetic acid and analyzed by LC-MS-MS. The with-in run precision, tested by pooling saliva samples from volunteers and then analyzing these in a single run, was found to be 7% at 0.7 microgram l(-1). The between-run precision was tested by analysis of the same samples at different days and found to be 11% at 2.5 microgram l(-1). The limit of quantification was 0.5 microgram l(-1). The method was applied for analysis of saliva samples from three volunteers during their last week before vacation and the first and second week on vacation. In addition, the method was compared to analysis by an immunological method. The values from the immunological method were 2.7 times higher than the LC-MS-MS results.

High incidence of mental disorders, reduced mental well-being and cognitive function in hypopituitary women with GH deficiency treated for pituitary disease

objective Previous studies have shown possible neuroendocrine effects of GH. In the present study we investigated the incidence of mental disorders and the prevalence of mental distress and cognitive dysfunction in hypopituitary women with untreated GH deficiency compared to population‐based controls.

Seasonal Variation in Human Salivary Cortisol Concentration

Measurement of cortisol concentration can contribute important information about an individuals ability to adjust to various environmental demands of both physical and psychosocial origin. However, one uncertainty that affects the possibilities of correctly interpreting and designing field studies is the lack of observations of the impact of seasonal changes on cortisol excretion. For this reason, the month‐to‐month changes in diurnal cortisol concentration, the awakening cortisol response (ACR), maximum morning concentration, and fall during the day were studied in a group of 24 healthy men and women 32 to 61 yrs of age engaged in active work. On one workday for 12 consecutive months, participants collected saliva at four time points for determination of cortisol: at awakening, +30 min, +8 h, and at 21:00 h. Data were analyzed by a repeated measures design with month (12 levels) and time‐of‐day (4 levels) as categorical predictors. Cortisol concentrations were analyzed on a log scale. The diurnal pattern of cortisol was similar across months (interaction between month and time of day: p>0.4). The main effects of month and time‐of‐day were statistically significant (p <0.001). Highest concentrations were observed in February, March, and April, and lowest concentrations were observed in July and August. There were no statistically significant effects in any of the other measures, or between men and women. In conclusion, a seasonal variation in salivary cortisol concentrations was detected in an occupationally active population. Thus, seasonal variation needs to be taken into account when designing and evaluating field studies and interventions and when making comparisons across studies.

The experience of pain from the shoulder-neck area related to the total body pain, self-experienced health and mental distress

The present paper presents the relationship between the total body-pain (TBP) score, defined as the total number of areas shaded on a pain drawing, and the pain from one area, the Shoulder-Neck (SN), among subjects in or out of full-time gainful work respectively. Furthermore, relationships between pain-score, self-experienced health (SEH) and level of mental distress, measured with the General Health Questionnaire (GHQ) were investigated. The analyses is based on a general population sample of 8,116 men and women, 45-60 years of age, completing a questionnaire in the Malmö Shoulder Neck Study. The TBP-score was higher with increasing pain from the SN area, being out of full-time work and among women. Independently of working status, the SEH decreased with increasing pain in the SN area, which was enhanced, by increasing TBP-score. The proportion of women out of full-time gainful work was twice as high as for men. Women showed the same SEH levels with regard to their pain status, independently of their working status while men working full-time scored higher than women did. Oppositely, men out of full-time work had the lowest SEH in relation to their pain status. The GHQ scores of mental distress varied essentially in the same way as the SEH did. The results emphasize the need for an assessment of the number of pain locations and which one that first gave symptoms when studying possible causal relationships between low force musculoskeletal load and development of localized pain. If such data are not collected in epidemiological studies on causes for musculoskeletal pain it will at best lead to unnoticed effect modifications. At worst a potential confounding situation may occur. The relationship between the self-experienced health, mental distress and chronic pain identifies chronic pain as a major public-health problem and suggests a multidisciplinary approach in the treatment and rehabilitation already before work capacity is lost.

Toluene in venous blood during and after work in rotogravure printing

SummaryToluene exposure was studied in 62 male rotogravure printers, employed in three plants. The exposure level as measured by personal sampling during a week ranged from 8 to 1080 mg/m3 (median 96). The concentration of toluene in venous blood sampled directly after work correlated significantly with the time-weighted average (TWA) for toluene in air during the preceding workshift (n = 57, Spearmans r = 0.84, P < 0.00001). The post-shift toluene level in venous blood is usable for biological monitoring of exposure. An air level of 100 mg/m3 corresponds to an average blood toluene level of 2.9 μmol/l; an air level of 300 mg/m3 to 8.2 μmol/l. The elimination of toluene is slow. Thus, toluene was detected in most Monday pre-shift blood samples and the levels increased statistically significantly during the work week (median 0.21 versus 0.42 μmol/l, P < 0.0001). The toluene level in venous blood sampled directly before work on Thursday/Friday was found to be a function of the estimated mean exposure during the work week. In a multiple linear regression analysis, the mean exposure during the week was a good predictor for the concentration of toluene in venous blood before work at the end of the week (n = 52, r = 0.71). Thus, pre-shift blood values at the end of the week can be used as a biological index for the weekly exposure, when the variation of the ambient toluene concentration is known. The slow decrease of toluene in venous blood was followed in six workers for two weeks after cessation of exposure. Two of them still had detectable amounts of toluene in blood after 13 d (detection limit = 0.01 μmol/l).

The Danish national return-to-work program - aims, content, and design of the process and effect evaluation

The Danish national return-to-work (RTW) program aims to improve the management of municipal sickness benefit in Denmark. A study is currently ongoing to evaluate the RTW program. The purpose of this article is to describe the study protocol. The program includes 21 municipalities encompassing approximately 19 500 working-age adults on long-term sickness absence, regardless of reason for sickness absence or employment status. It consists of three core elements: (i) establishment of multidisciplinary RTW teams, (ii) introduction of standardized workability assessments and sickness absence management procedures, and (iii) a comprehensive training course for the RTW teams. The effect evaluation is based on a parallel group randomized trial and a stratified cluster controlled trial and focuses on register-based primary outcomes - duration of sickness absence and RTW - and questionnaire-based secondary outcomes such as health and workability. The process evaluation utilizes questionnaires, interviews, and municipal data. The effect evaluation tests whether participants in the intervention have a (i) shorter duration of full-time sickness absence, (ii) longer time until recurrent long-term sickness absence, (iii) faster full RTW, (iv) more positive development in health, workability, pain, and sleep; it also tests whether the program is cost-effective. The process evaluation investigates: (i) whether the expected target population is reached; (ii) if the program is implemented as intended; (iii) how the beneficiaries, the RTW teams, and the external stakeholders experience the program; and (iv) whether contextual factors influenced the implementation. The program has the potential to contribute markedly to lowering human and economic costs and increasing labor force supply. First results will be available in 2013. The trial registrations are ISRCTN43004323, and ISRCTN51445682.

A comparison of neuropsychological tests for the assessment of chronic toxic encephalopathy

BACKGROUND From the viewpoint of the clinical neuropsychologist, it is not evident if the detection of solvent induced toxic encephalopathy (TE) could be optimized by a modification of the traditional test batteries, adding tests covering new dimensions or monitoring further functional domains. METHODS To clarify this issue, TE patients were re-examined with (a) the tests traditionally used in screening for TE and (b) some tests hitherto less utilized within neurotoxicology, involving complex attention and frontal lobe functioning. RESULTS The results do not indicate that tests of the latter category would be more sensitive to TE than the tests traditionally used. Using an optimized core battery, compiled of tests from both categories, the sensitivity and specificity levels reached a maximum of around 0.7 when using as criterion the reproduction of a subnormal test profile (TE type 2B). CONCLUSIONS A combination of several traditional and a few newer tests is suggested to optimize the detection of TE. Repeated assessments over time are also recommended.

Adult survivors of childhood acute lymphoblastic leukaemia with GH deficiency have normal self-rated quality of life but impaired neuropsychological performance 20 years after cranial irradiation.

Objective  Cranial radiotherapy (CRT) was, until recently, important for achieving long‐term survival in acute lymphoblastic leukaemia (ALL). Because survival rates have improved markedly, the long‐term complications, such as GH deficiency (GHD) and neuropsychological impairment, have become increasingly important.

Cortisol, sleep, and recovery — Some gender differences but no straight associations

BACKGROUND Work related fatigue has been suggested as a link in the assumed sequence of events between repeated adverse work demands and the development of work related stress, which may be associated with changes in concentrations of cortisol, psychological overload and, in the long run, health problems. Insufficient sleep is a contributing factor to lack of recovery, but previous studies on associations between subjective aspects of sleep and recovery, and cortisol, have been inconclusive. The aim with the present study was to examine possible associations between cortisol measures and (I) self-rated recovery, (II) occupational fatigue and (III) subjective sleep quality the night preceding cortisol sampling. Further, possible gender differences were tested. METHODS Salivary cortisol was measured in 581 persons during a working day, at awakening, +30 min and in the evening. Various measures of subjective sleep and recovery were analyzed in relation to cortisol. RESULTS Few correlations between cortisol and any sleep- or recovery parameters were found. However, some significant associations were found between cortisol and a few measures of more chronic aspects of sleep and recovery. Gender stratified analyses showed somewhat differing associations among men and women. This indicates that possible associations and pathways between lack of recovery/sleepiness and cortisol, and in the long run, unhealth, may not be similar for men and women.